Claude Desktop App Setup

How to use Roblox MCP with the Claude Desktop App.

Prerequisites

• Claude Desktop App installed
• Node.js (v18.0.0 or higher)
• Roblox Studio plugin installation complete

Registering the MCP Server

Method 1: Desktop Extensions (Recommended)

Available from 2026 — one-click install like a browser extension

1. Claude Desktop → Settings → Extensions
2. Search for weppy-roblox-mcp
3. Click Install

Method 2: Edit Config File Directly

1. Claude Desktop → Settings → Developers → Edit Config

2. Add the following to claude_desktop_config.json:

{
  "mcpServers": {
    "weppy-roblox-mcp": {
      "command": "npx",
      "args": ["-y", "@weppy/roblox-mcp"]
    }
  }
}

3. Fully quit Claude Desktop and restart it

Config file location:

Connection Test

1. Launch Roblox Studio → Plugins tab → WEPPY → Connect
2. Start a new conversation in Claude Desktop and test:

   Create a blue Part in Roblox Studio

Troubleshooting

MCP Server Not Loading

1. Check JSON syntax: Validate the config file with an online JSON validator
2. Fully restart Claude Desktop: After changing config, always quit the app completely and restart it
3. Check the path: Confirm the command and args are correct

Server Won’t Start

Run the MCP server directly to see the error:

npx -y @weppy/roblox-mcp

Connection Fails

• Confirm the Roblox Studio plugin shows Connected status
• Check that port 3002 is not blocked by a firewall